U.S. Pat. No. 5,777,891 by Pagano et al (hereinafter the “'891 patent”), hereby incorporated by reference as if fully disclosed herein, teaches ultrasonic real-time inspection methods which are user-friendly, interactive, as well as providing a combination of consistency, thoroughness, and speed of operation in flaw detection not achievable by methods previously known.
The methods taught by the '891 patent offer significantly increased pattern recognition capability compared to the prior art, and have greater automation potential and reduced missed detection and false alarm rates. The methods taught by the '891 patent are adaptable for use in a rail inspection system for examining railroad rails for flaws and identifying flaws in the rail in real-time. The rail inspection system repetitively and regularly injects pulses of ultrasonic beams into the rails from test devices mounted on a vehicle traveling along the rails. Acoustic echoes caused at rail discontinuities (such as a joint in the rails) are detected within the test devices to produce electrical signals representative of the magnitude of the acoustic echoes. The travel times of the acoustic echoes to the place of injection are determined, and deriving from the travel times, angles of travel, beam pulse speeds, and beam spreads of the ultrasonic beams inside the rails, spatial signals representative of the locations of the discontinuities along the rails are obtained. The system then combines spatial signals located within the rails to identify and locate flaws in and along the rails. Information representative of normal patterns of known rail discontinuities, are stored by the system. This information is compared to the combined spatial signals to detect and identify unknown discontinuities (which are flaws) and to eliminate and reclassify those discontinuities inconsistent with recognized context, and indicating the locations of said rail discontinuities.
It is an objective of the instant invention to expand and improve on the teachings of the '891 patent, by providing a novel method for differentiating ultrasonic reflections during real-time analysis in an ultrasonic inspection system.
It is another object of the invention to provide a method for using pattern recognition rules to detect and classify indications in real-time non-destructive testing.
It is a related object to provide tools for the building, analysis and management of these pattern recognition rules.
It is a further object of the invention to provide methods for recognizing indications in the test article by using a multi-stage decomposition analysis process.
It is another object of the invention to provide an easily adaptable system that can be adapted for different test conditions.
Another object is to utilize algorithms based on a two-phase analysis to provide context-sensitive analysis against a sequence of test data. A related object is to utilize the algorithms for finding and classifying anomalies from an input data set, and to sort data based on certain criteria.